1. Field Of The Invention
This invention relates to agricultural seed planting machines and is primarily directed to the closing wheel mounting arrangement for closing the furrow side walls over the planted seed.
2. Description Of The Prior Art
Heretofore, agricultural seed planters have been equipped with furrow forming disks in association with a pair of furrow closing wheels for closing the furrow, by moving the displaced soil at respective sides of the trench thus formed, over the seeds planted in the furrow, but such closing wheels have always been suspended from the planter frame in pairs, so that they moved up and down together as either wheel encountered some obstacle and deflected both wheels regardless of which side of the furrow the obstacle was found.
Some early patents disclosed closing wheels suspended by means of a pivoted arm which was deflectable against the pressure of a biasing spring, such as Myers U.S. Pat. No. 835,031, but this concept appeared to utilize but one closing wheel which necessarily had to engage soil on both sides of the furrow to close soil over the seeds in the trench.
Similarly, expired patent to McIntyre U.S. Pat. No. 2,704,524 discloses a single "packer wheel 37" that is pivotally suspended by means of a spring biased arm 40 but here it is quite obvious tht the wheel 37, as shown in FIG. 2 of the patent, is sufficiently wide to straddle the trench formed by the disk 27, the leading edge of which is aligned with approximately the median position of the packer wheel tread.
Existing patent to Truax U.S. Pat. 4,030,428 discloses a seed drill for planting native grass type seeds and includes an arrangement wherein a number of press wheel assemblies 56 are each disposed in alignment with a pair of converging disks which open the furrow to form a trench into which the seeds are fed and then these seeds are ridden over by the press wheels but it must be noted that only one press wheel is provided for each furrow and more importantly the press wheels are each fixedly mounted so that there can be no deflection according to ground conditions.
Stacy U.S. Pat. No. 4,070,974 discloses a disk type trench filler wherein the disk-like filler 10 trails behind a disk opener 26, in alignment therewith and is provided with oppositely curving, alternately extending segments 11 and 12 which engage the soil at respectively opposite sides of the trench, or furrow, to press the walls of the trench inwardly over the planted seeds. Here again only the one presser wheel is provided and while it is pivotally mounted for vertical deflection by means of the trailing arm 28 it has no independent action at opposite sides of the furrow.
Peterson U.S. Pat. No. 4,244,306 discloses a single "packer wheel 32" for each double disk opener 31 and is located behind the opener in alignment therewith so that it becomes apparent that it cannot function at respectively opposite sides of the furrow.
Early patent to Vivion U.S. Pat. No. 1,007,256 discloses an arrangement typical of old prior planter devices involving a furrow opener 2 and a pair of rigidly mounted, spaced disks 16 which have no means of spring biased vertical deflection but the gauge of the disks may be adjusted by means of the wedge-shaped block 20 disposed between the respective mounting arm 13 and the gauge plates 3. No provision is made for pivoting of the arms 13 mounting the disks 16 so that it is not possible for the disks to be deflected vertically in response to ground variations.
U.S. Pat. No. 4,009,668 to Brass et al. shows two closing wheels inclined relative to each other and operative at opposite sides of a seed trench but these wheels are both mounted on a rigid axle member that is bent to adapt to the inclination of the wheels and supported in a single arm that is pivotally mounted on the main frame to preclude independent wheel movement.